What is bile duct cancer?

How cancer starts

Cancer is when abnormal cells start to divide and grow in an uncontrolled way. The cells can grow into surrounding tissues or organs and may spread to other areas of the body.

Find out more about cancer and how it starts

The bile ducts

The bile ducts are part of the ​digestive system​. They are tubes that carry bile from your liver, where it is made, to your gallbladder, where it is stored. Bile is a fluid that helps your body digest food. 

When you eat, your gallbladder releases bile back into the bile ducts. It flows to the small bowel where it breaks down fat in the food you've eaten. This makes it easier for your body to use the food. 

This video shows where the bile ducts are, what they do and the different areas where bile duct cancer can develop. The video is 1 minute and 30 seconds long. 

There 2 main bile ducts in the liver. These are the:

• right hepatic duct

• left hepatic duct

They join together just outside the liver to make the common hepatic duct. Bile flows down this duct and into the cystic duct. This is connected to the gallbladder.

When we eat, bile is released from the gallbladder back into the cystic duct. It then flows down the common bile duct.

Before it gets to the small bowel, the common bile duct joins the pancreatic duct. This releases pancreatic juice which also breaks down food to make it easier to use.

Where bile duct cancer develops

Doctors divide bile duct cancer into 3 groups depending on where it starts:

• intrahepatic bile duct cancers

• perihilar bile duct cancers

• distal bile duct cancers

Intrahepatic bile duct cancer

Starts in the bile ducts inside the liver. It is a type of ​primary​ liver cancer. 

Intrahepatic bile duct cancer is also called intrahepatic cholangiocarcinoma.

Perihilar bile duct cancer

Starts in the bile ducts just outside the liver, but before the cystic duct joins the common hepatic duct.

Perihilar bile duct cancer is also called a Klatskin tumour or hilar cancer.

Distal bile duct cancer

Starts in the bile ducts below where the cystic duct joins the common hepatic duct. 

Find out more about the different types of bile duct cancer

Who gets bile duct cancer?

Anything that can increase your risk of cancer is called a risk factor. Having one or more risk factors doesn’t mean you'll definitely get bile duct cancer.

Bile duct cancer is more common in older people. The risk is also higher in people who have:

• inflammation in their bile ducts called primary sclerosis cholangitis (PSC)

• a rare type of ​cyst​ in their bile ducts called a choledochal cyst

• stones in their bile ducts or gallbladder - these are made from tiny amounts of fats and ​bilirubin​

Some other risk factors can depend on which bile duct the cancer is in and where in the world you live.

Read more about the risks and causes of bile duct cancer

How common is bile duct cancer?

In the UK, around 3,100 people are diagnosed with bile duct cancer each year. 

The number of people getting bile duct cancer has increased in the last few years. Researchers don't know for sure what's causing the number to increase. Some studies suggest it might be related to lifestyle choices such as smoking and drinking alcohol.